Abstract
The study of coal liquefaction has been conducted since 1988 using NEDOL 1 t/d Process Supporting Unit (PSU) and the coal slurry operation time has reached 20, 000 hours. In this period, five kinds of coals, Taiheiyo, Wandoan (Australia), Illinois No.6, Wyoming (U. S. A), Tanito Harum (Indonesia) were used and the reaction conditions for the high oil yield were investigated. Moreover, the character-istics of the coal liquefaction catalyst were also invesigated. And the new operational information obtained and the new operational technology were developed.
In high calcium content coal, the formation mechanism of the deposited solid was elucidated and the withdrawal method of the deposited solid was determined.
In high ferric and sulphur content coal, formation mechanism of the deposited solid to the slurry preheater was elucidated and the prevention countermeasure was studied. In high moisture content coal, the plugging at the slurry preparation line occured and the mechanism of the increasing of the slurry viscosity was elucidated and the prevention countermeasures were studied. These operational analyses and developement will be re-flected to the operation of the scale up coal liquefaction plants in future.
